Declaring the prison overcrowding crisis "a distant memory," Gov. Jerry Brown has moved to end federal court orders forcing California's prison system to shed thousands of inmates and improve medical and mental health care deemed inhumane just three years ago.

In court papers filed this week, he urged a special federal court panel to set aside a sweeping August 2009 order that already has prompted the nation's largest prison system to release more than 30,000 inmates. The panel ordered the state to reduce crowding to 137.5 percent of "design capacity."

Prison crowding is now below the 150 percent threshold at the state's 33 prisons, Brown said. More than half of the decline has happened since October 2011 because of the Public Safety Realignment, which housed low-level criminals in local jails instead of prison.

At San Quentin State Prison, the reported population on Monday was 3,967, or 128 percent over capacity, according to the state prisons department. That was down about 23 percent from early January 2009, when the population was 5,164, or 167 percent above capacity. In early January 2006, the prison had 5,433 inmates, or 148 percent above capacity.

Brown and state prison officials argue that California has done enough to fix its prisons and bring inmate health care up to legal standards. They warned that keeping the prisons under court control threatens public safety and could cost the state billions of dollars more as it tries to emerge from its most severe budget crisis in recent history.

"California is a powerful state," Brown said Tuesday. "We can run our own prisons. And by God, let those judges give us our prisons back."

But the governor's legal maneuver, which he vowed to press to the Supreme Court if necessary, raised many of the same arguments that have fallen flat in previous attempts to avoid federal court intervention in the state prison system. The question now is whether California can prove prison overcrowding has diminished enough to persuade the courts to step aside and end a legal quagmire that has dragged on for decades.

Prisoner rights lawyers called the Brown administration's legal arguments frivolous and plan to challenge the request to dissolve the court orders. They argue that health care remains dismal in California's prisons as a result of continuing overcrowding.

"The problem is that rather than fixing the problems, the state is just playing a litigation game," said Rebekah Evenson, a staff attorney with the Prison Law Office.

A three-judge panel had given the state until midnight Monday to reveal how it would finish the task of reducing prison overcrowding. But in court papers, the governor's administration instead argued that "continued enforcement of the order is unfair, unnecessary and illegal."'

The court in 2009 found California's prisons were so overcrowded that they violated the constitutional rights of the prisoners by failing to provide adequate mental health and medical care for inmate population that at times exceeded 160,000.

Federal judges Thelton Henderson, Lawrence Karlton and Stephen Reinhardt found that inmates were regularly dying as a result of poor medical care.

The court ordered the state to reduce the inmate population to 137 percent of capacity within two years, a ruling upheld in 2011 by a divided Supreme Court.

State officials say they've reduced the prison population by 26,000 inmates since October 2011, when the governor's realignment plan went into effect, shifting many low-level offenders, such as probation violators, to county jails, and by more than 36,000 inmates since lawyers on both sides presented their original arguments in 2008. Prison reports show the inmate population at its lowest level since May 1995.

As of two weeks ago, the prisons remained at 149 percent of its capacity, despite the reduction in the overall inmate population. But in court papers, state officials maintain they have spent hundreds of millions of dollars improving the prison health care system and reducing overcrowding, from an $840 million prison health facility in Stockton set to open in July to a $29.5 million treatment center at Salinas Valley State Prison.

The governor said county jails should not be asked to absorb any more inmates.